| | 1 | .\" Copyright (c) 1986, 1991, 1993 |
| | 2 | .\" The Regents of the University of California. All rights reserved. |
| | 3 | .\" |
| | 4 | .\" Redistribution and use in source and binary forms, with or without |
| | 5 | .\" modification, are permitted provided that the following conditions |
| | 6 | .\" are met: |
| | 7 | .\" 1. Redistributions of source code must retain the above copyright |
| | 8 | .\" notice, this list of conditions and the following disclaimer. |
| | 9 | .\" 2. Redistributions in binary form must reproduce the above copyright |
| | 10 | .\" notice, this list of conditions and the following disclaimer in the |
| | 11 | .\" documentation and/or other materials provided with the distribution. |
| | 12 | .\" 4. Neither the name of the University nor the names of its contributors |
| | 13 | .\" may be used to endorse or promote products derived from this software |
| | 14 | .\" without specific prior written permission. |
| | 15 | .\" |
| | 16 | .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| | 17 | .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| | 18 | .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| | 19 | .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| | 20 | .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| | 21 | .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| | 22 | .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| | 23 | .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| | 24 | .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| | 25 | .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| | 26 | .\" SUCH DAMAGE. |
| | 27 | .\" |
| | 28 | .\" @(#)sleep.3 8.1 (Berkeley) 6/4/93 |
| | 29 | .\" $FreeBSD: src/lib/libc/gen/sleep.3,v 1.17 2007/01/09 00:27:55 imp Exp $ |
| | 30 | .\" |
| | 31 | .Dd February 13, 1998 |
| | 32 | .Dt SLEEP 3 |
| | 33 | .Os |
| | 34 | .Sh NAME |
| | 35 | .Nm sleep |
| | 36 | .Nd suspend process execution for an interval measured in seconds |
| | 37 | .Sh LIBRARY |
| | 38 | .Lb libc |
| | 39 | .Sh SYNOPSIS |
| | 40 | .In unistd.h |
| | 41 | .Ft unsigned int |
| | 42 | .Fn sleep "unsigned int seconds" |
| | 43 | .Sh DESCRIPTION |
| | 44 | The |
| | 45 | .Fn sleep |
| | 46 | function suspends execution of the calling process until either |
| | 47 | .Fa seconds |
| | 48 | seconds have elapsed or a signal is delivered to the process and its |
| | 49 | action is to invoke a signal-catching function or to terminate the |
| | 50 | process. |
| | 51 | System activity may lengthen the sleep by an indeterminate amount. |
| | 52 | .Pp |
| | 53 | This function is implemented using |
| | 54 | .Xr nanosleep 2 |
| | 55 | by pausing for |
| | 56 | .Fa seconds |
| | 57 | seconds or until a signal occurs. |
| | 58 | Consequently, in this implementation, |
| | 59 | sleeping has no effect on the state of process timers, |
| | 60 | and there is no special handling for SIGALRM. |
| | 61 | .Sh RETURN VALUES |
| | 62 | If the |
| | 63 | .Fn sleep |
| | 64 | function returns because the requested time has elapsed, the value |
| | 65 | returned will be zero. |
| | 66 | If the |
| | 67 | .Fn sleep |
| | 68 | function returns due to the delivery of a signal, the value returned |
| | 69 | will be the unslept amount (the requested time minus the time actually |
| | 70 | slept) in seconds. |
| | 71 | .Sh SEE ALSO |
| | 72 | .Xr nanosleep 2 , |
| | 73 | .Xr usleep 3 |
| | 74 | .Sh STANDARDS |
| | 75 | The |
| | 76 | .Fn sleep |
| | 77 | function conforms to |
| | 78 | .St -p1003.1-90 . |
| | 79 | .Sh HISTORY |
| | 80 | A |
| | 81 | .Fn sleep |
| | 82 | function appeared in |
| | 83 | .At v7 . |
projects / apple / libc.git / blame_incremental